Astro Tuesday: Juliana Garcia-Mejia (Harvard CFA) and Amanda Bauer (Yerkes Observatory)

12:00–1:00 pm ERC 401

Host: Austin Joyce

Juliana Garcia-Mejia (Harvard CFA) "First Light Results from the Tierras Observatory, An Ultra-precise Time-series M-dwarf Photometer"

We have refashioned the 1.3m 2MASS telescope located at the F.L. Whipple Observatory atop Mount Hopkins, Arizona, into an ultra-precise time-series photometer: The Tierras Observatory. Tierras is designed to achieve a photometric precision of 250 ppm across an observing season. The design choices that enable this precision include a four-lens focal reducer and field-flattener to increase the field-of-view of the telescope from 0.19 deg to 0.50 deg on a side; a custom narrow (40 nm) bandpass filter centered around 863.5 nm to minimize precipitable water vapor errors known to limit ground-based photometry of M dwarfs; a deep-depletion 4k × 4k CCD with a quantum efficiency of 85% in our bandpass, operating in frame transfer mode; and, a fully automated observing mode. Tierras achieved first light in the fall of 2021, and in February 2022 we installed a new set of baffles to significantly reduce sky background. We will share recent light curves and summarize our current on-sky performance. Tierras is starting a three-year survey of M dwarf stars within 15 parsecs to detect new terrestrial planets that were too small or too cool to be found by TESS or previous ground-based efforts, and to monitor known exoplanets (both rocky and gaseous) to search for satellites or systems of circumstellar rings. Furthermore, a long term monitoring campaign will permit Tierras to determine M dwarf rotation periods, elucidating the process and timescale over which these stars lose their angular momentum.

Amanda Bauer (Yerkes Observatory) "Yerkes Observatory: 125 Years of History and a Bright Future"

Yerkes Observatory is known globally as the birthplace of modern astrophysics and remains the home to the world’s largest refracting telescope. It was founded in 1897 and run by the University of Chicago until 2020, when the Yerkes Future Foundation (YFF) assumed long-term stewardship for the Observatory and its landscape. YFF has raised a significant portion of its initial $30M goal and has invested that in restoration, major construction work, and building the staff and programs. The Yerkes Future Foundation is committed to a future where Yerkes Observatory inspires creativity through exploration, art, and a connection with the cosmos, so imagination, collaboration, and scientific curiosity thrive and transform the world. Our mission is to ensure Yerkes continues to advance astronomy and to transform the Observatory and its grounds into a destination for science and discovery—an experience unlike any other where science, environment, culture, arts, and curiosity pollinate in novel and unique ways. In this conversation, I'll let you know how we plan to do this and what opportunities exist for you.

Event Type


Jan 24